1. Cytology
The study of cells

2. 1) Procaryotic 2) Eucaryotic
Cell Types
1) Procaryotic
2) Eucaryotic

3. Procaryotic Cells Cells lack a true nucleus
Cells have only non-membrane bound organelles
Bacteria and some algae

4. Eucaryotic Cells Cells have a true nuclues
Cells have membrane bound organelles
Most protists
All fungi, plants, animals, and humans

5. 1) Boundary 2) Cytoplasm 3) Nucleus
Cellular Structures
1) Boundary
2) Cytoplasm
3) Nucleus

6. Cellular Boundaries Plasma membrane Cell wall Middle lamella
Capsule / sheath / slime coat

7. Plasma membrane The outermost boundary of all cells Semi-permeable
Phospholipid bilayer
Proteins are embedded within
transportation
cell recognition
cell adhesion

8. Plasma membrane

9. Laminin video clip by louie giglio

10. Cell wall Rigid structure surrounding some cells Porous
all procaryotes
plants, algae, fungi, and protozoans
Porous
Composed of cellulose or chitin

11. Middle lamella Layer between two adjacent cell walls
Acts as a lubricant

12. Capsule / Sheath / Slime coat
A cellular secretion of polysaccharides
Surrounds unicellular or colonial organisms
Protective
Attackers must first dissolve the capsule or penetrate it

13. Cytoplasmic Organelles
Cytoplasmic matrix
Ribosomes
Endoplasmic reticulum
Mitochondria
Plastids
Golgi body
Lysosomes
Vacuoles
Centrioles
Flagellum
Cilia

14. Cytoplasmic Matrix (aka: the cytoplasm)
Located in all types of cells
A semi-solid watery substance in which all other organelles are suspended
Think “jello salad”
Provides structure to the cell thanks to its cytoskeleton
Cytoplasmic streaming – contents are always moving

15. Ribosome Located in all types of cells Mass of proteins and RNA
Function: protein synthesis

16. Endoplasmic Reticulum
Seen only in eukaryotic cells
Folds of cellular membranes
Continuous with both the plasma membrane and the nuclear membrane
Functions:
Provide flexible but structural shape
Synthesis of proteins, lipids, & polysaccharides
Movement of substances throughout the cell

17. Types of ER’s

18. Mitochondria Seen only in eukaryotic cells
A double-membrane bound bean shape structure
Inner membrane is folded to form cristae
Function: cellular respiration
Quantity is dependent on the activity level of the cell

19. Mitochondria

20. Plastids Seen only in plants and algae
A double-membrane bound structure
Function: synthesis and storage of polysaccharides

21. Types of Plastids Chromoplasts
Contains the pigments used in synthesizing polysaccharides
Given specific names based on the type of pigment in the chromoplast
Most important chromoplast: the chloroplast (green pigment)

22. Chloroplast Inner membrane is folded to form the thylakoid
Stack of thylakoids is called a grana
Fluid within the chloroplast is called stroma

23. Types of Plastids Leucoplasts Colorless structure
Function: a storehouse of starch
Most numerous in the fleshy, storage areas of plants

24. Golgi body Seen only in eukaryotic cells
A flat, curved, membrane structure
Function:
Synthesizing polysaccharides
Final modifications of proteins & lipids for their final destination

25. Lysosome Seen only in eukaryotic cells
Small, membrane bound spherical structure
Contains digestive enzymes
Function:
digestion of old, used organelles
digestion of invading cells

26. Vacuoles Seen only in eukaryotic cells Function: storage
4 types of vacuoles
Phagocytic
Pinocytic
Waste
Contractile

27. Types of Vacuoles Phagocytic Pinocytic Waste Storage of food
Formed by phagocytosis
Pinocytic
Storage of water
Formed by pinocytosis
Waste
Storage of nondigestible material
Fuses with the plasma membrane to release material

28. Types of Vacuoles Contractile vacuole
Found in unicellular organisms that live in a freshwater environment
Collects excess water and pushes the water back out of the cell

29. Centriole Seen only in eukaryotic cells, except plants
2 cylinders occurring at right angles to each other
Always located near the nucleus
Function: cell division

30. Flagellum Located in all types of cells
Long, tubular extension of the cytoskeleton within the cytoplasm
Small quantity: usually have 1 – 4 flagella on a cell
Function: locomotion of the cell

31. Cilia Located in all types of cells
Short extensions of the cytoskeleton
Usually covers the entire cell or a large section of a cell
Function: locomotion of the cell or movement of substances within an organism

32. Internal Structure of Cilia & Flagella
Both have the same internal structures
Both structures have been used to disprove evolution
Irreducibly complex

33. Nucleus (the control center of the cell)
Nuclear envelope
Chromatin material
Nucleolus

34. Nuclear Envelope Seen only in eukaryotic cells Porous
Phospholipid bilayer
Continuous with the endoplasmic reticulum

35. Chromatin Material Seen in all types of cells
Long, thin strands consisting of DNA and proteins
Function: codes for the information needed for protein synthesis
DNA permits activity of a cell, but it does not decide what the cell is capable of doing
DNA was programmed by God at creation

37. Nucleolus
An area with a large concentration of RNA (a substance similar to DNA)

38. Review of Cellular Structures